The invention relates to a method for manufacture of an optoelectronic coupling element.
Designing the housing of one element with an integrated hollow cylinder as a receptacle and the housing of the second element as a plug, and inserting the plug directly into the receptacle in order to optically connect two optoelectronic elements, is known from German patent DE 36 30 382 Al. Furthermore, providing the element designed as a plug with a housing of a commercially available LED is also known from this publication. The housing shape of the element provided as the receptacle is known from optoelectronic elements used for coupling and uncoupling of an optical signal in an optical waveguide. To increase the optical coupling factor, at least one of the two elements is provided with a lens. The two housing sections are manufactured using standard methods, such as casting, pressing and injection molding, as known from LED production.
Since the optoelectronic elements are accommodated in complete housings and are surrounded on all sides by the housing material, these housings are best comprised of transparent, light-permeable material. This results in a not inconsiderable emission of the luminous power from the transmitter to the outside. Added to the problem of insufficient coupling is that of extraneous light incidence from the outside, which further reduces the quality of an optocoupler of this type. To make the housing optically tight, a second outer housing is provided that completely surrounds the first housing. However, these measures necessitate a number of additional production steps.